The Russian moles booted from the United States in a sensational spy swap last week are on the hot seat with their Moscow bosses — who want to “know how their cover could have been blown,” it emerged yesterday.

“If it turns out that serious mistakes were made, spies . . . can be fired,” a source told the newspaper Moskovsky Komsomolets.

The sloppy sleepers are being grilled in a special Foreign Intelligence Service compound in Moscow, the paper said.

They are being given lie-detector tests, and are not allowed to use devices for outside communication, such as cellphones, sources said.

Details of the spies’ post-assignment interrogation came as:

* American authorities deported a 12th suspected mole: a 23-year-old Russian man who was living in the western United States and whose “name came up” in the FBI’s probe of the other spies shortly after he arrived here in October, a law-enforcement official said.

But the man, identified as Alexey Karetnikov, is not part of the same spy ring as the other 11, sources insisted.

* Sexy spy Anna Chapman’s British citizenship, obtained by a prior marriage to an Englishman, was revoked.

* El Diario reported that its Peruvian-born op-ed columnist, Vicky Pelaez — one of the 10 agents — lied about her birth date, her wedding date to a fellow spy, her name, her dad’s name and the length of time she’d been living in the United States when she obtained residency papers.